From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,50137bb64a119cfc X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-02-10 14:27:57 PST Path: archiver1.google.com!postnews1.google.com!not-for-mail From: rod.chapman@praxis-cs.co.uk (Rod Chapman) Newsgroups: comp.lang.ada Subject: Re: "access constant" discriminant Date: 10 Feb 2003 14:27:57 -0800 Organization: http://groups.google.com/ Message-ID: References: NNTP-Posting-Host: 213.152.53.239 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1044916077 9883 127.0.0.1 (10 Feb 2003 22:27:57 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: 10 Feb 2003 22:27:57 GMT Xref: archiver1.google.com comp.lang.ada:33971 Date: 2003-02-10T22:27:57+00:00 List-Id: tmoran@acm.org wrote in message news:... > Can this be done? How? A great shame that it can't. From the viewpoint of a static analysis tool, this is dreadful, since access parameters don't specify whether the referenced objected is intended to be referenced, updated, or both - this severely limits our ability to do information flow analysis in the presence of access parameters, which needs such information to be available as part of a subprogram's specifiction if it to used usefully and efficiently implemented. In light of this, SPARK currently excludes access parameters. (In SPARK, we have parameter modes as normal, but we extend a subprogram's specification to include a list of all global data and their import/export modes via the global annotation. This makes IFA efficient, since we don't need to look inside the body - all the info we need is on the spec.) If access parameters were allowed to specify such information (e.g. "access in", "access out" and "access in out") this would be a great help. I remember mentioning this to Tucker at SigAda and he took a note of it - not sure if this issue has made it into any of the current AI's, though... - Rod